In general, a mobile terminal is configured to perform various functions. These various functions include video and voice call communications, capturing still or moving images using a camera, storing voice, reproducing music file(s) through a speaker system, displaying image or video, etc. Some mobile terminals include additional functions such as playing games, and other mobile terminals are implemented as multimedia players. Moreover, recent mobile terminals are configured to allow a user to view video or television programs by receiving broadcast or multicast signals.
Various attempts have been made to implement enhanced functions of the mobile terminal not only by structural improvements, but also by hardware or software improvements. A touch function of the mobile terminal allows a user having a difficulty in inputting buttons or keys to conveniently operate the mobile terminal by using a touch screen. Recently, this touch function is considered as an important function of the mobile terminal, together with a User Interface (UI) as well as a simple input function. As the touch function is applied to the mobile terminal in various ways, developing a suitable UI is required to a larger extent.
The mobile terminal provides a user with a Location-Based Service (LBS). The LBS may include a radio contents service for informing a user of his measured position, or specific information regarding the measured position.
Positioning using the LBS often includes a satellite-based positioning method for performing positioning based on a signal received from a satellite, and a base station-based positioning method for performing positioning based on a positional relationship between a base station and a mobile terminal. The satellite-based positioning method is advantageous in that the accuracy is high, and positioning can be performed while a user is moving since the mobile terminal is not influenced by a radio network environment.
Global Navigation Satellite System (GNSS) satellites which provide information on a position, an elevation, a speed, etc. of an object by using a satellite, include the Chinese COMPASS under development, the Japanese QZSS, the European Galileo, etc., as well as the American GPS and the Russian GLONASS. It is expected that the number of GNSS satellites will be more than 100 in 2013.
If the same type of satellites are used (e.g., if the number of GPS satellites increases), the accuracy of positioning is enhanced. However, if different types of GNSS satellites are used, a dilution of precision (DOP) increases. That is, as the number of satellites increases, signals of more densely arranged satellites are received, thereby lowering the accuracy of positioning.
Further, in the conventional art, signal strengths of GNSS satellites should be checked so that a specific satellite can be selected from a plurality of satellites. This may increase battery consumption (power consumption) of the mobile terminal.